A closed-loop proportional-integral-derivative (PID) control algorithm can be tuned to have a response time (e.g., accelerated response time) to meet the control requirements of a fluid flow application. But, tuning the response time of a closed-loop PID control algorithm to meet the requirements of a specific application can have undesirable side-effects. For example, a closed-loop PID control algorithm that is tuned as a fast algorithm to respond quickly to sudden, significant changes in the flow of a fluid may cause noisy flow when fluid flow is stable. A fast algorithm amplifies high frequency sensor, analog-to-digital converter (ADC) quantization, and electronics noise, resulting in noisy control signals.
A closed-loop PID control algorithm, on the other hand, tuned to have a slow response time may not introduce noise into a stable fluid flow, but may not be able to accurately and quickly correct for sudden, significant changes in flow conditions (e.g., sudden changes in set point or changes in pressure). The problems associated with implementing only a fast or a slow response time algorithm can be complicated by non-idealities such as, for example, lagging flow sensor readings or non-linearities in flow controller components. Accordingly, a need exists to address the shortfalls of present methodologies and to provide other new and innovative features.